Electric-motor drive



Feb. 17,1925.

F. H. CLOUGH ELECTRIC MOTOR DRIVE Filed June 12, 1922 Inventor: j wed ericl-lforion (7015972 WW,@M

Patented Feb.'17, 1925.

UNITED STATES PATENT OFFICE.

FREDERICK H. CLO'UGH, OF HILLIVIORTON, NEAR RUGBY, ENGLAND, ASSIGNOR- TO GENERAL ELECTRIC COMPANY, A CORPORATION OF NEW YORK.

ELECTRIC-MOTOR DRIVE.

Application filed June 12, 1922.

To all 10710222 it may concern:

Be it known that I, FREDERICK HORTON CLoUcH, a subject of the British Empire, residing at Hillmorton, near Rugby, England, have invented certain new and useful Improvements in and Relating to Electric- Motor Drives, of which the following is a specification.

This invention relates to electric motor drives and is particularly applicable to the driving of machinery having parts designed to rotate at slightly different speeds.

In certain kinds of machinery, for eX- ample, machinery used in the preparation and spinning of cotton, there are two shafts or other members which rotate at approximately the same speed, but in which there a small difference in speed which has to be controlled. Casesof this kind occur in slubbers and intermediate flyers, rovers and liy frames, and it is the custom to arrange the separate shaftsconcentrically one inside the other and to drive them separatelyat different speeds, for example, to employ differential mechanism to enable the difference in the speed to be controlled or to drive one member by friction from the other and to apply a braking mechanism to the frictionally driven member to produce the necessary retardation. I

The present invention provides electrical apparatus for driving such members at slightly different speeds, and to effect this purpose according to the invention, the members are driven by a motor having two rotors, one driving each of the two abovementioned shafts or other members.

For a better understanding of my invention, reference may be had to the following description taken in connection with the accompanying drawing, in which the single figure shows a machine having an electric motor drive in. accordance with my invention.

The drawing illustrates my electric drive for a machine employed for spinning flax or similar material. The central vertical spindle 1 has fixed at its upper end the flyer frame 2. Surrounding the spindle 1 and concentric therewith is a tubular shaft 3 upon the upper part of which the bobbin upon which the fibre is to be wound is placed. It will be realized that it is necesry o drive the sp d e 1 and he hollow Serial No. 567,721.

shaft 3 at slightly different speeds in order to enable winding to take place. The hollow shaft 3 will be driven at a slightly smaller speed than the spindle 1.

According to the invention this drive is effected by means of a motor such as an induction motor 4, the stator of which to which power is supplied being shown at 5. The spindle 1 forms the shaft of the rotor 6 which is of similar construction to a small squirrel cage armature and as there is practically no load upon the spindle 1, the latter will be rotated at substantially the synchronous speed corresponding to the frequency of the supply to the stator 5.

The tubular shaft 3 at its lower end carries a spider 7 which carries conductor bars which are located in the air gap between the stator 5 and central rotor 6. These conductors form a second rotor which would rotate at the same speed as the rotor 6 when the tubular shaft 3 is unloaded. \Vhen winding is going on, however, the drag of the fibre such as hemp or cotton yarn increases the slip of the second rotor so that the shaft 3 rotates at a slightly smaller speed than the spindle 1 and independently thereof.

It is well known that the actual slip of an induction motor can be changed by varying the voltage supplied to the winding of the stator 5 and in accordance with the present invention, the difference in speed between the spindle 1 and the hollow shaft 3 can be adjusted to any desired extent by varying the voltage supplied to the stator winding.

Other forms of motors can be employed according to the invention, for example, the rotor may consist of an iron core with definite poles produced either by permanent magnets or direct current windings. In this case the central rotor will rotate at synchronous speed. The second rotor revolving in the air gap may in the case of such a small motor consist of a metal cylinder. Furthermore, the rotors may be placed side by side within the stator.

W'hile' this type of drive is peculiarly suitable for use in connection with spinning machinery, the invention is not limited to such an application, but it may be employed wherever it is required to drive two members of a machine at slightly different speedsl v 7 parts adapteol to rotate atslightly different shaft,thegojherpart oflsaid inachine being Whatylplaim as new andd esire to secure motor, a shaft driyen by one of said rotors by,Lett r fi s b he nite ,L et l i ='i; an 1 h hl i'o sac parts of said 1. In combination, a machine having two I machine is mounted, "a second shaft surrounding the first mentioned shaft and driven by the other'of said rotors at -aspeed different from said first mentioned shaft, a motor having a single stator and two rotheother part of said machine being mounttors designed to operate at slightly different ed oiisaid second shaft. speeds, one of saidrotors being conne cted 5 111 combination, a machine having two to and adapted to driye one part of said parts aaaptearo' rotate at slightly different m ch and the othe o a rqt r ibe connected to the other part' of said machine and adapted to, drive said other part at a different, speed from said first mentioned :P I'F- 5 speeds, said parts being 'ciapabl'e ofinde pendent rotation with respect to each'other,

pendent rotation with respect to each' other, moto-rf haying a si'n glefst-ator and two ersf i ,offf ict rbtoif eiha lo t in A a i fine:anga btweea 11e stator and the other I 2. In combinationpa na-chinel aying twojrotor, Jone, offsaid" rotors being" connected parts, adapted to rptate at slightly different it ana' aaapta tq arive one part of said speeds said parts being capable of indemachine and'the other of 'saidirotorslb'eing ipendent rotation spect to eachiothei, connectedto the other part jof sa id machine a moto har ing a singlels tatoi W11 two mf adapted'to drive s'aid'fotherpart'at a i otors designed to operate at slightlyfiifir; ditferent speedfrom said first mentioned t speec ls a-shaft .driye11 by one; oflsaid' part. A i p Q V otorsland onwhich one o t said "parts of I w r "iiiatiliiiie'hai'fing two .isaid, rnachine is monnted, secondjfshaft" parts adapted to retateia slightly 'd'ifierent surronnding the first; mentioned sli a ft Qand'f speed's', ah'alternating c'urrenfiniotor ham d riyen by theother vo1 sai d rot ors at sing efstator and two ifotors','on'e of lifferent -speed from: said first' nientioned' aidrotors being-located in'tlie airjgap bep H tweenthe'stator and thefoth'errotor and bemonnted on $21 1 vsecondjshaft I ing d'riyen astli e "rotor of an'indnction 3 ,11; combination, afmao'hine having two finotoiflfoneof said"rotorsbeing"connected parts adapted to rotateatisl ightly 'di fier-[ tolfon'e' par'tfof'sjaid machine and the other em e m -raf s ina ara b i de n e .ret tle a We r sp t reach other analternating current motor having woof said 'Iotoi f's j being" "connected to the other ypartof said' nachlne. I V o 7,. In 'coIIib11iat1on,' :a"mach nelraving two 3 5 single stator and rwdietdr jone of said parts a'daptedto iotate atsli ghtlydifl'erent .i. it \1 'v 1 i vi' v i 11' V i-rotors being driyen as therotor, of an 111- speeds, an al e ating current motor having dnction motor pone ofsladl rotors being 'conv v I .a singl'e' st atorfandtwo rotors, one ofsaid nected to and adapted to drive one part of rotors beil'i g' doca'ted J inthe air gap between ,saidpniachine, and the ot-her of 'said rotors the f stator and the' other'frotor and being pe in connected tdtlieotherpart ot said driven as' 'a' rotor of anindu'ction motor, machineandYadapted to, drive fs'aid otheipa shaft on v which one 'of sa'idrotors and part ajt a diflerent speed from said first' biie'ofisaid parts'of saiclmacliine are mount- 1,1DQ11t-l0 ljlQCLP3Itl v t V t t etl,1asecondfshaftsiirronnding the first men- 4.; In combination a; machine having two tioned sharta'ncrdn which the other of said i 5 f partsta daptedjto fllot'ate at slightlydifferent rot'c'frs and theother'part of said machine eeds saijdfparts"fbeingfcapablje of inde memeuad,

an alternating'cfirrent inotor haying 'agsingle my hand "tlii's'twentyfifth day of May, 1922. v stator and two rotors, one of said rotors j 'FRED. Hi GLOUGH.

,.- l?? 1dent;rotat1onw th-respect't' ea chother, In"wltnessfwliereof, I'ha-Ve hereunto set being driven asthe rotorof an induction 

